From: Rayagonda Kokatanur <rayagonda.kokata...@broadcom.com>

Add NIC I2C support to the iProc I2C driver. Access to the NIC I2C base
registers requires going through the IDM wrapper to map into the NIC's
address space

Signed-off-by: Rayagonda Kokatanur <rayagonda.kokata...@broadcom.com>
Signed-off-by: Ray Jui <ray....@broadcom.com>
---
 drivers/i2c/busses/i2c-bcm-iproc.c | 79 ++++++++++++++++++++++++++++--
 1 file changed, 75 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c 
b/drivers/i2c/busses/i2c-bcm-iproc.c
index 5b9cbd7a3776..9598e1d0048e 100644
--- a/drivers/i2c/busses/i2c-bcm-iproc.c
+++ b/drivers/i2c/busses/i2c-bcm-iproc.c
@@ -17,9 +17,11 @@
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 
+#define IDM_CTRL_DIRECT_OFFSET       0x00
 #define CFG_OFFSET                   0x00
 #define CFG_RESET_SHIFT              31
 #define CFG_EN_SHIFT                 30
@@ -174,11 +176,26 @@ enum bus_speed_index {
        I2C_SPD_400K,
 };
 
+enum bcm_iproc_i2c_type {
+       IPROC_I2C,
+       IPROC_I2C_NIC
+};
+
 struct bcm_iproc_i2c_dev {
        struct device *device;
+       enum bcm_iproc_i2c_type type;
        int irq;
 
        void __iomem *base;
+       void __iomem *idm_base;
+
+       u32 ape_addr_mask;
+
+       /* lock for indirect access through IDM */
+       spinlock_t idm_lock;
+
+       /* indicates no slave mode support */
+       bool no_slave;
 
        struct i2c_adapter adapter;
        unsigned int bus_speed;
@@ -215,13 +232,33 @@ static void bcm_iproc_i2c_enable_disable(struct 
bcm_iproc_i2c_dev *iproc_i2c,
 static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
                                   u32 offset)
 {
-       return readl(iproc_i2c->base + offset);
+       u32 val;
+
+       if (iproc_i2c->idm_base) {
+               spin_lock(&iproc_i2c->idm_lock);
+               writel(iproc_i2c->ape_addr_mask,
+                      iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
+               val = readl(iproc_i2c->base + offset);
+               spin_unlock(&iproc_i2c->idm_lock);
+       } else {
+               val = readl(iproc_i2c->base + offset);
+       }
+
+       return val;
 }
 
 static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
                                    u32 offset, u32 val)
 {
-       writel(val, iproc_i2c->base + offset);
+       if (iproc_i2c->idm_base) {
+               spin_lock(&iproc_i2c->idm_lock);
+               writel(iproc_i2c->ape_addr_mask,
+                      iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
+               writel(val, iproc_i2c->base + offset);
+               spin_unlock(&iproc_i2c->idm_lock);
+       } else {
+               writel(val, iproc_i2c->base + offset);
+       }
 }
 
 static void bcm_iproc_i2c_slave_init(
@@ -766,7 +803,13 @@ static int bcm_iproc_i2c_xfer(struct i2c_adapter *adapter,
 
 static uint32_t bcm_iproc_i2c_functionality(struct i2c_adapter *adap)
 {
-       return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SLAVE;
+       struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adap);
+       u32 val = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+
+       if (!iproc_i2c->no_slave)
+               val |= I2C_FUNC_SLAVE;
+
+       return val;
 }
 
 static const struct i2c_algorithm bcm_iproc_algo = {
@@ -829,6 +872,8 @@ static int bcm_iproc_i2c_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, iproc_i2c);
        iproc_i2c->device = &pdev->dev;
+       iproc_i2c->type =
+               (enum bcm_iproc_i2c_type) of_device_get_match_data(&pdev->dev);
        init_completion(&iproc_i2c->done);
 
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -836,6 +881,26 @@ static int bcm_iproc_i2c_probe(struct platform_device 
*pdev)
        if (IS_ERR(iproc_i2c->base))
                return PTR_ERR(iproc_i2c->base);
 
+       if (iproc_i2c->type == IPROC_I2C_NIC) {
+               res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+               iproc_i2c->idm_base = devm_ioremap_resource(iproc_i2c->device,
+                                                           res);
+               if (IS_ERR(iproc_i2c->idm_base))
+                       return PTR_ERR(iproc_i2c->idm_base);
+
+               ret = of_property_read_u32(iproc_i2c->device->of_node,
+                                          "brcm,ape-hsls-addr-mask",
+                                          &iproc_i2c->ape_addr_mask);
+               if (ret < 0) {
+                       dev_err(iproc_i2c->device,
+                               "'brcm,ape-hsls-addr-mask' missing\n");
+                       return -EINVAL;
+               }
+
+               spin_lock_init(&iproc_i2c->idm_lock);
+               iproc_i2c->no_slave = true;
+       }
+
        ret = bcm_iproc_i2c_init(iproc_i2c);
        if (ret)
                return ret;
@@ -992,7 +1057,13 @@ static int bcm_iproc_i2c_unreg_slave(struct i2c_client 
*slave)
 }
 
 static const struct of_device_id bcm_iproc_i2c_of_match[] = {
-       { .compatible = "brcm,iproc-i2c" },
+       {
+               .compatible = "brcm,iproc-i2c",
+               .data = (int *)IPROC_I2C,
+       }, {
+               .compatible = "brcm,iproc-nic-i2c",
+               .data = (int *)IPROC_I2C_NIC,
+       },
        { /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, bcm_iproc_i2c_of_match);
-- 
2.17.1

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